1. Field of the Invention
The present invention relates to an image generating device, an image generating method, and an information storage medium.
2. Description of the Related Art
There is an image generating device for generating in real time a three-dimensional motion picture representing a motion of an object in accordance with an input of a user. A motion picture is expressed by switching still pictures each time a given time elapses. Each of the still pictures that form the motion picture is called “frame”. An image generating device generates images of those frames by using action data, which is information on a posture of an object in accordance with time. The image generating device samples, from the action data, the posture of the object at the time (sampling time) corresponding to the frame, and outputs image data on the frame indicating the posture of the object.
An interval between the sampling time for a given frame and the sampling time for the subsequent frame normally has a fixed value or is caused to change depending on an actual calculation time of processing for generating the image of the frame.
In that case, a characteristic of the action sometimes does not appear in the image of each frame depending on a relationship between an action of the object and the interval between the sampling times. For example, with regard to a jumping action of the object, the frame for expressing an instant at which a peak of the jump is reached sometimes does not exist, resulting in a failure to express a height by which the object has jumped. Further, there is a fear that a collision or contact that should take place may not happen if a result of performing the sampling from the action data is used for collision judgment. In addition, for example, in a case of a rotational motion of a wheel, the wheel sometimes appears to be rotating reversely if a time interval between the frames becomes longer for some reason.